Circuit controlling device



Sept. 30, 1952 A. B. RYPlNsKl CIRCUIT CONTROLLING DEVICE Filed June 7.1947 /MA-TALL/C 'INVENTOR A4 fer/3: RnQ//VJK/ ATTORNEY Patented Sept.30, 1952 UNITED STATES PATENT orties y CIQRCUT CONTROLLING DEVICE AlbertB. Rypinski, Laurelton, N. Y., assgnor to Metropolitan DeviceCorporation, Brooklyn, N. Y., a corporation of New York Appliance .time'1, 1947, serial No. 753,193

(ci. zoo- 88) 3 Claims. 1

The invention herein disclosed relates to a circuit controlling devicethat may be operated manually to open and close an electrical circuit,but which operates automatically to open a closed circuit upon continuedoverloads and short circuits. More particularly, the invention relatesto a circuit breaker of the kind mentioned in which a movable switchelement is retained against the action of biasing means by a -detent andreleasable latch. y

An object of the invention is to provide a ciru cuit breaker of the kindmentioned in ywhich a magnetically affected element is forciblyattracted to the latch and in a direction to release the latch upon asudden rise in current flowing through the circuit breaker. Anotherobject of the invention is to provide a circuit breaker of the kindmentioned in which a magnetically affected element is forcibly attractedto a bimetallic latch upon a sudden rise in current flowing through thebimetallic latch so that on short circuit, the latch is rapidlyreleased.

The foregoing objects and certain advantages inherent in the inventionthat will hereinafter appear are realized in the embodiment of theinvention illustrated in the accompanying drawing and described indetail below, from which description a clear understanding of theinvention may be had.

The drawings include:

Fig. 1 which is a plan of a circuit breaker embodying the invention;

Fig. 2 which is a transverse section of the same taken on the line 2--2of Fig. l;

Fig. 3 which is a sectional, side elevation taken on the line 3 3 ofFig. l.;

Fig. 4 which is a sectional, side elevation taken on the line 4-4 ofFig. l;

Fig. 5 which is an enlarged, side elevation of the movable switchelement, partly broken away; and

Fig. 6 which is a sectional elevation of the same taken on the line '6-6of Fig. 5.

The circuit breaker illustrated in the drawings essentially includes a`case and operating Aparts that are housed within the case. The case Afor the circuit breaker is open at the bottom and has an opening Ithrough the top for a finger piece 2 by means of which the circuitbreaker may be manually actuated. .A base B serves as a closure for thebottom of the case and as a support for stationary contacts 3 and 4,associated with connecting pieces 5 and 6 and termif nals 'I and 8.These case and base together form a complete enclosure for the circuitbreaker except for vents 9 and Ill extending vertically through the caseto permit the free passage of gases generated by arcs formed within thecase.

The operating mechanism, in general, includes two movable elements, amanually operative element or handle C from which the finger piece 2extends, and a switch element or rotor D. The handle consists of adisk-like wall II from which a shaft I2, formed integral therewith,extends. An axially extending flange I3 is formed at one portion of thehandle, the outer portion in the assembled circuit breaker, and extendsfrom the wall I I.` The nger piece 2 extends radially from this flangethrough the opening in the case. The rotor is partially encased withinthe handle and is rotatably mounted upon the shaft I2 which in turn isrotatably mounted in a slide i4 received in a complementary groove inone side wall of the case, and in the arcuate end of a slot l5 in theopposite side wall.

A spring element acts upon the handle and rotor to eiect independentmovement thereof towards off or open-circuit position. This springelement consists of tWo torsional spring sections I6 and il, one on eachside of a central loop i8 extending substantially tangentially of thespring. The end of the spring section i6 is received in a groove orkeyway in the shaft I2 and the end of the section I'I is received in agroove in the rotor. Under normal conditions, the handle, when moved tothe on position, is restrained against the action of the spring sectionI6, which acts to urge the handle toward 01T position, by a latchinglever I9 that enters in a recess 2i) in the flange on the handle andengages the end wall of the recess.

This latching lever IS` is resiliently urged into latching relation withthe end of the slot or recess 20 by the spring loop I8 which engages thelatching end of the lever. The lever is pivoted between its ends upon apivot pin 2| that extends from the slide Ill in which` the shaft I2 isjournaled. A cam surface 22 on the rotor is arranged to engage the end23 of the lever when the rotor moves to off position. Upon engagement ofthe end of the lever by the cam surface 22, the lever is withdrawn fromthe recess in the handle and the handle is thus released to move to offposition under the action of the Aspring section I6.

The rotor, normally, is latched, in a manner hereinafter described, tothe handle so that when the handle is moved to on circuit position, therotor moves with the handle. Likewise, the latching arrangement is suchthat if the handle be" moved to off circuit position, the rotor underthe action of the spring section Il will follow the handle to the offposition.

The rotor carries switch contacts 24 and 25 which engage respectively,in the on position, with the stationary contacts 3 and 4. When the rotormoves to the "off circuit position, the contacts 24 and 25 move awayfrom the stationary contacts. Normally, the section I1 of the spring andthe stationary contacts exert a force tending to rotate the rotor to theoi position. The stationary contacts are mounted and arranged so as tohave a certain amount of resiliency and are positioned with respect tothe contacts on the rotor so that they are under tension in the oncircuit position of the rotor.

The rotor is provided with current-releasable means for effecting therelease of the rotor from the handle upon continued overloads or shortcircuit. It is with this current releasable means, as arranged in acircuit breaker of this kind, that the invention of this application isprimarily concerned.

The latching arrangement by which the rotor n is normally secured to thehandle includes a detent 26 and a bimetallic element 21. The detentconsists of a dog-pointed, hardened set screw that is threaded in anopening in the iiange I3, and it extends from the flange parallel to theaxis of circuit breaker mechanism. The end 28 of the set screw acts as adetent and is engaged, under normal conditions by the detentengaging end29 of the bimetallic element 2?..

Each of the rotor contacts 24 and 25 has a reduced rounded extension, 30and 3| respectively, which passes through the rotor wall. The endsections of these extensions are further reduced in diameter and haveanged, insulating bushings, such as the bushing 32 (Fig. 6) thereon, andthe ends of the bimetallic element 21, which is substantially of theshape of an inverted V, are securedon these extensions between theiianges of the bushings and headed-over ends of the extensions. The endsof the bimetallic element are thus secured at the face of the rotor andelectrically connected to the contacts 24 and 25, i. e. the bimetallicis connected across the contacts so that current through the breakerflows through the bimetallic element. The detent-engaging end section 29of the bimetallic element extends radially to a point beyond the end 28of the set screw 26. One edge of the detent-engaging end section, thatwhich engages the detent, is cut away as shown to conform to the shapeof the detent, and the edge may be rounded to provide a point contactwith the detent and so minimize friction tending to retard warping ofthe bimetallic element. The opposite edge of the detent-engaging endsection is wedge-shaped and bent away from the detent to form a lead-inand so permit ready relatching after the bimetal has escaped and cooled.Under bias of the spring, the bimetal engages in latching relation thedetent end 28 of the screw 26 to effect movement of the rotor with thehandle, under normal conditions, from open-circuit to closed-circuitposition. By turning the screw 26, the extent of engagement between thebimetallic element and detent may be adjusted.

The bimetallic element is held away from the face of the rotor as shown.Between the bimetallic element and the rotor an iron armature 33, in theshape of an inverted V, is mounted on the insulating bushings (32, Fig.6) on the extensions 30 and 3l so that it may pivot thereon. The ironarmature is shaped the same as the bimetallic element, except that it iswithout a detent-engaging end section.

The normal operation of the circuit breaker is by the heating andwarping of the bimetallic element. This heating and warping occurs whenexcess current passes through the bimetallic element. When warped thebimetallic element becomes released from the detent and releases therotor. On a sudden rise in value of the current, such as occurs on shortcircuit, the magneticv field set up by the current in the bimetallicelement causes the hinged iron armature to be. attracted at its freeend, as any armature. is attracted by a solenoid, and the armaturedelivers a blow to the bimetallic element at the detent-engaging sectionthereof and in the direction to free the bimetallic element from thedetent. If perchance the blow delivered by the armature is insufficientto free the bimetallic element immediately, its pressure on thebimetallic element will follow the pulsations of the alternatingcurrent,v and the combined warping ofthe bimetallic element and themagnetic vibratory pressure will quickly disengage it.

When the bimetallicv element is released from the detent, either bywarping, by a blow from the armature.. or by both, the rotor or switchelement moves, under the action of the spring to off circuit position.Movement of the rotor releases latching lever I9, and the handle followsthe rotor to off circuit position where the rotor and handle arerelatched through the bimetallic element. If the release of thebimetallic element occurred by virtue of a blow from the armature, therelatching may occur immediately; if it occurred by warping of thebimetallic element, then the bimetallic element must cool beforerelatching occurs.

From the foregoing description of the embodiment of the inventionillustrated in the drawing, it will be apparent. that by this inventionthere is provided a circuit breaker in which a magnetically `affectedarmature is forcibly attracted to the releasable latch in a direction torelease the latch and effect a rapid opening in the breaker on a sudden.rise in the value of the current or on short circuit.

It will be ovious that various changes `may be made by those skilled inthe art in the details of the embodiment of the invention illustrated inthe drawings and described indetail above within the principle and scopeof the invention as deiined in the appended claims.

I claim:

1. In a circuit controlling device of the kind described, thecombination comprising a movable switch element, spaced switch contactscarried by the switch element, a bimetallic element carried by theswitch element, connected across the switch contacts and having adetent-engaging end section movable with respect to the switch element,bias means for moving the switch element in one direction, a detentpositioned to retain the switch element against movement under theaction of said bias means when engaged by the detent-engaging endsection of the bimetallic element, and a magnetically attracted armaturepivotally mounted on the switch element and positioned to be forciblyattracted to and strike the detent-engaging end section of thebimetallic element in a direction to release the bimetallic element fromthe detent upon a sudden rise in current flowing through the bimetallicelement.

2. In a circuit controlling device of the kind described, thecombination comprising a movable switch element, spaced switch contactscarried by the switch element, a bimetallic element carried by theswitch element, connected across the switch contacts and having adetent-engaging end section movable with respect to the switch element,bias means for moving the switch element in one direction, a fixeddetent positioned to retain the switch element against movement underthe action of said bias means when engaged by the detent-engaging endsection of the bimetallic element, and a magnetically attracted armaturebetween the switch element and the bimetallic element, and plvoted onthe switch element and positioned to be forcibly attracted to and strikethe detent-engaging end section of the bimetallic element in a directionto release the bimetallic element from the detent upon a sudden rise incurrent flowing through the bimetallic element.

3. In a circuit controlling device of the kind described, thecombination comprising a movable switch element, spaced switch contactscarried by the switch element,` a bimetallic element carried by theswitch element, connected across the switch contacts and having adetent-engaging end section movable with respect to the switch element,bias means for moving the switch element in one direction, a fixeddetent positioned REFERENCES CITED The following references are ofrecord in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,812,842 Sachs June 30, 19312,260,583 Rypinski Oct. 28, 1941 2,312,169 Jackson Feb. 23, 19432,325,717 Swingle Aug. 3, 1943 2,389,999 Rypinski Nov. 27, 1945 FOREIGNPATENTS Number Country Date 597,445 Germany May 25, 1934

